Postoperative nausea and vomiting (PONV) is common in pediatric patients undergoing surgery, with an incidence ranging 40-70% of patients undergoing tonsillectomy. It may be associated with various adverse consequences. Various medications have been suggested for the prevention of PONV. The effectiveness of these medications in children undergoing tonsillectomy, as well as in surgical patients in general, is variable. There is no established standard for the prevention of PONV in children undergoing tonsillectomy. Moreover, the administration of these agents may be associated with side effects and with an increased cost. Failure of an effective pharmaceutical antiemetic regimen, and concerns regarding the side effects and the high cost of newer drugs, have led practitioners to examine the use of nonpharmacologic techniques such as acupuncture and acupressure for the prevention of PONV. Simplicity, lack of side effects and low cost may offer advantages of acupuncture over "conventional" therapeutic regimens. Efficacy of acupuncture or acupressure in the treatment or prevention of PONV has been demonstrated in some, but not all, randomized controlled trials. Several problems such as the importance of applying the pressure at a specific acupoint (versus a non-acupoint location) were not evaluated in these studies. The purpose of this study is to evaluate the effectiveness of acupuncture and acupressure as antiemetic prophylaxis in children undergoing tonsillectomy.